As manufacturers expand their reach into more diverse global markets, Qalitex Laboratories, an Irvine-based provider of scientific testing services for dietary supplements and personal care products, is calling attention to the need for zone-specific stability testing.
While many product formulations pass standard stability protocols, they may not account for the environmental extremes of regions such as Southeast Asia, the Middle East, or Central Africa—raising questions about the accuracy of shelf-life claims under real-world conditions.
Standard Testing Protocols and Their Limitations
Most manufacturers rely on the International Council for Harmonisation (ICH) guidelines when validating the stability of their products.
These guidelines define both real-time (25°C ± 2°C / 60% RH ± 5%) and accelerated (40°C ± 2°C / 75% RH ± 5%) testing conditions, which are widely accepted for product registration across North America, Europe, and other temperate regions.
While these conditions provide a reliable baseline, they do not reflect the higher temperatures or humidity levels common in tropical or arid climates.
This becomes relevant when the same product is shipped and sold in global markets with vastly different environmental conditions than the ones simulated in a stability chamber.
Climatic Zones and Regional Variations
The World Health Organization (WHO) recognizes four primary climatic zones to guide region-specific stability testing:
- Zone I – Temperate climate
- Zone II – Subtropical and Mediterranean climate
- Zone III – Hot and dry climate
- Zone IVa/IVb – Hot and humid climate
In some countries—particularly those in Zones III and IV—regulatory authorities may require manufacturers to conduct stability testing at 30°C and relative humidity levels up to 75%.
This data helps demonstrate whether a product will maintain its quality and safety throughout its shelf life under local storage conditions.
Cosmetics, personal care products, and topical supplements are among the product categories that may be affected.
In these cases, zone-specific requirements do not always follow pharmaceutical regulations but may still be enforced under consumer protection and safety guidelines.
Shelf-Life Claims Under Environmental Stress
If testing conditions fail to reflect the actual environment where the product is sold, the stated shelf life may no longer be valid.
Elevated temperatures can accelerate chemical degradation, while high humidity can compromise preservation systems or trigger microbial growth—particularly in formulations with natural ingredients or insufficient antimicrobial hurdles.
Even physical characteristics like separation, caking, or viscosity changes can arise under stress conditions, leading to potential non-conformances or product returns.
In the worst-case scenario, degradation could pose a health or safety risk if microbial or chemical stability is lost.
“Microbial stability tells you whether a product can actually hold up over time without becoming a risk,” said Nour Abochama, Vice President of Operations at Qalitex.
“If you’re making shelf-life claims, you need data that proves the formula stays within safe microbial limits, start to finish.”
Packaging Stability Also Affected
In addition to product formulation, packaging materials themselves can respond poorly to climate extremes.
For example, plastic containers can warp or soften in excessive heat, compromising the integrity of the product seal.
In humid zones, internal moisture-absorbing components like desiccants may reach capacity too early, allowing condensation to affect stability.
These risks may not be detected in stability studies designed for Zone II conditions.
As a result, manufacturers entering markets in Zones III and IV are advised to evaluate both product and packaging under stress conditions relevant to their target regions.
Regulatory Scrutiny and Documentation Readiness
Some national regulators have already begun asking for zone-specific data during registration or post-market audits, particularly in the Middle East, Southeast Asia, and parts of Africa and South America.
In some cases, documentation must demonstrate stability at 30°C/65% RH or 30°C/75% RH for a minimum of six months.
While not all jurisdictions require this data, the trend suggests a shift toward environmental relevance in testing programs—especially when local authorities are concerned about consumer protection in climates where degradation is more likely.
Preparing for Global Market Expansion
Manufacturers expanding into new markets should evaluate whether their existing stability studies are sufficient for regulatory and practical needs.
This may involve mapping their target countries to WHO climatic zones and identifying any documentation gaps for real-time or accelerated data at the appropriate conditions.
Teams responsible for regulatory compliance, quality assurance, and product development should collaborate early to build testing programs that align with where the product will actually be distributed.
Where needed, supplemental studies can be conducted under alternative zone conditions to support label claims or update shelf-life documentation.
“Many brands have stability data that works for temperate climates,” said Abochama. “But when they start looking at new regions—especially hot and humid ones—they may realize the data doesn’t go far enough.”
Closing the Gap Between Testing and Reality
Stability testing is a critical tool not only for registration, but for maintaining consumer trust and safety.
As the regulatory landscape continues to evolve, especially across global e-commerce platforms, manufacturers may face increased scrutiny around whether their documentation reflects real-world distribution.
“Climatic zone testing isn’t about overcomplicating compliance,” Abochama added. “It’s about making sure your product really does what the label says—wherever it ends up.”
